Patent awarded to quantum cooling company
GIBRALTAR -- Cool Chips plc, a company seeking to develop an innovative approach to thermoelectric cooling based on quantum tunneling principles, has been awarded U.S. patent No. 6,417,060 entitled "Method for Making a Diode Device". The company is due to present details of its technology at the 21st International Conference on Thermoelectrics August 25-29, 2002, to be held at the Hyatt Regency Hotel, Long Beach, California.
The patent, the most recent of a family of patents assembled since 1995, refers to a method for manufacturing energy conversion devices based on the tunneling of electrons across a vacuum gap of nanometer-scale.
The company, with contacts and connections in the U.S. and Canada but registered in the British colony of Gibraltar on the Spanish coast, is a majority-owned subsidiary of Borealis Explorations Ltd., also registered in Gibraltar.
The devices are a form of vacuum diode that transfers heat from one side of the chip to the other to provide localized cooling and refrigeration. The technology is solid state and operates silently without the use of motors or environmentally unfriendly fluids. If successfully developed wafers from Cool Chips promise efficiency levels much higher than existing solid-state cooling systems, the company said.
Such features could be useful in aerospace applications where space and weight are key.
The Cool Chips technology has been evaluated by the Phantom Works advanced R&D division of Boeing Corp. Boeing announced last year that it had negotiated the right of first refusal on the technology for aerospace applications.
The method of manufacture involves creating a nanometer-scale gap between two electrodes. An electrode is coated with a sublimative material such as cadmium and then a second electrode is deposited on top. Because the cadmium layer is very thin, any surface variation on the lower electrode will be mirrored on the upper, deposited electrode, so a constant gap is maintained between the two. When the upper surface has been deposited, the device is heated in a vacuum chamber from which the sublimative layer is removed as a vapor.
"This is a new, elegant method for manufacturing matched pairs of electrodes and maintaining a consistent gap at the nanometer level. We are now building increasingly compact devices and continually improving our manufacturing techniques as we drive towards commercial production prototypes," said Cool Chips' president Isaiah Cox, in a statement.
The upcoming paper, to be presented by Avtandil Tavkhelidze, is entitled "Preliminary Results on Electron Tunneling Through Large Area Vacuum Gaps".
In it Tavkhelidze is due to describe how the Cool Chips researchers have obtained tunneling currents of over 10-A through the vacuum between conformal electrodes. The paper will discuss measured current-voltage (I-V) characteristics of the system, and demonstrate that capacitance and conductance dependence on the distance between electrodes is also in good agreement with a simple model of electrodes separated by a vacuum gap, the company said.
A presentation of the Cool Chips technology could be found at a third party's web site here at the time this article was first posted.
A number of presentations of the Cool Chips technology could be found at Cool Chips's web site here shortly after this article was first posted.